Flight time - Battery heat and condition

[Cyberphox]

Hi all,

I am quite a newbie with electric RC aircraft. My son and I have converted an old Flair piper cub to electric. we fitted the following:

ripmax quantum II 40 brushless motor
Skywalker 60A ESC with BEC
Radiant superpax 4s 14.8v 3200mAh
Prop size 12x8

The system can only run for 3.5 min at full throttle, is this normal? The battery is quite hot ( I need to measure it) I suppose this could be normal considering the motor sucks 60A. My glow engine in a similar setup gives me 15min flight time.

Any tips and suggestions most welcome

thanks
M

 

[tntpoof]

hard to give correct info back without kv and C rating of battery

 

[Tunedfrog]

Seems a bit short of run time to me..

 

[Rolex]

How big is the plane? A Piper Cub is not a stunt flyer or a performance plane and full throttle shouldn't be used except for take off.

 

[tntpoof]

its a 7 lb plane . with that prop and no other info ...

 

[Cyberphox]

hard to give correct info back without kv and C rating of battery

Thanks for replying, the battery is 30C. For the motor I don’t know it’s KV

http://www.ripmax.com/Item.aspx?ItemID=M-Q2-40

 

[Cyberphox]

How big is the plane? A Piper Cub is not a stunt flyer or a performance plane and full throttle shouldn't be used except for take off.

It has a wingspan of 1.8m and weighs 3.14kg with battery.

I was testing it on the ground to get an idea on its limits. Sure normally the stick would not be on full throttle. The reason is that on its first flight it stopped really early so thought to check it out on land

Thanks

 

[Cyberphox]

It has a wingspan of 1.8m and weighs 3.14kg with battery.

I was testing it on the ground to get an idea on its limits. Sure normally the stick would not be on full throttle. The reason is that on its first flight it stopped really early so thought to check it out on land

Thanks

How big is the plane? A Piper Cub is not a stunt flyer or a performance plane and full throttle shouldn't be used except for take off.

Hi all,

I am quite a newbie with electric RC aircraft. My son and I have converted an old Flair piper cub to electric. we fitted the following:

ripmax quantum II 40 brushless motor
Skywalker 60A ESC with BEC
Radiant superpax 4s 14.8v 3200mAh
Prop size 12x8

The system can only run for 3.5 min at full throttle, is this normal? The battery is quite hot ( I need to measure it) I suppose this could be normal considering the motor sucks 60A. My glow engine in a similar setup gives me 15min flight time.

Any tips and suggestions most welcome

thanks
M

I ran a second trial this time I went full throttle for 5-7secs to simulate take off and then mid throttle for normal flight.

This time I get 8 mins which is a bit more acceptable. what do you think?

Battery less hot too.

Will take it out and fly next.

 

[Rolex]

so thought to check it out on land

Well, now, that says a lot. Full throttle, full load with no forward movement. Of course it heated up and gave you short run time. Even at mid throttle it's under additional load without forward movement.

 

[tntpoof]

I just read all this and go UGH. Newbie bigtime..

 

[Cyberphox]

As it says in the original thread, I am a newbie. Hence the post for some help. ?

 

[Rolex]

We know you're new. Now you also know why you got limited time and a hot battery. Time to go fly it and enjoy it.

 

[Cyberphox]

Indeed, that is very true and I am very grateful for the nudges in the right direction ?

Took it out to fly it today, the motor was fine. I also rearranged the ESC for better ventilation. The next item is there is a bit of work to optimise the control surface trims. The transmitter trims were near the end stops which is not good.

Thanks for the help

 

[tntpoof]

There is bench testing along with adjustment .1st thing to do.servo centering with zero trim set . sorry I forgot your are new do you have a buddy that can be you safety flyer
https://www.modelaircraft.org/sites/default/files/105.pdf
do you have a buddy cable and a buddy pilot setup for your 1st flight if not get 1.. do you have any sim experience on rc plans?

 

[Tunedfrog]

Highly recommend this. Because I used this for a solid month or better before I flew the first time, my first flight was flawless.

 

[Cyberphox]

There is bench testing along with adjustment .!st thing to do.servo centering with zero trim set . sorry I forgot your are new do you have a buddy that can be you safety flyer
https://www.modelaircraft.org/sites/default/files/105.pdf
do you have a buddy cable and a buddy pilot setup for your 1st flight if not get 1.. do you have any sim experience on rc plans?

I took it to a field with some more experienced flyers took it up and who me to get the trims better centred on the bench.

Once this is sorted I should be able to buddy up with a cable.

I was looking at RF10 simulator but it doesn’t allow you to use your own controller, instead you have to buy the one they supply. But it might be worthwhile considering how easy it is to crash.

I am based in the UK ?? we have a similar setup as AMA but under the BMFA. The rules are quite strict and you can’t fly wherever you want etc.

 

[Tunedfrog]

Mine is the RF9 and I can use my Spektrum DX6E but haven't yet. I've came to the conclusion that surface RCs are more my thing than planes, but I still use the sim often.

 

[Cyberphox]

Oh I believe Realflight works with spectrum but won’t with Futaba

 

[tntpoof]

Thats also why filling out your profile and all the information it askes is a Good thing.. so I dont need to Guess,,..lol...